BlackRock Fund Advisors’s ION Geophysical Corporation IO Stock Holding History

Bought

Maintained

Sold

Quarter	Market Value	Status	Shares	Change in Stake	Trade Value	Portfolio Weight	Portfolio Position
2016 Q4	$160K	Buy	26,672 +784	+3%	+$5.37K	﹤0.01%	3485
2016 Q3	$177K	Sell	25,888 -43	-0.2%	-$248	﹤0.01%	3486
2016 Q2	$162K	Sell	25,931 -209,558	-89%	-$1.57M	﹤0.01%	3529
2016 Q1	$1.9M	Sell	235,489 -11,141	-5%	-$64.9K	﹤0.01%	3092
2015 Q4	$1.86M	Sell	246,630 -307,475	-55%	-$2.19M	﹤0.01%	3164
2015 Q3	$3.24M	Buy	554,105 +20,215	+4%	+$213K	﹤0.01%	2986
2015 Q2	$8.57M	Buy	533,890 +4,577	+0.9%	+$123K	﹤0.01%	2600
2015 Q1	$17.2M	Buy	529,313 +23,129	+5%	+$830K	﹤0.01%	2143
2014 Q4	$20.9M	Buy	506,184 +65,997	+15%	+$2.6M	0.01%	2043
2014 Q3	$18.4M	Sell	440,187 -21,000	-5%	-$1.12M	0.01%	2011
2014 Q2	$29.2M	Sell	461,187 -32,351	-7%	-$2.04M	0.01%	1787
2014 Q1	$31.2M	Buy	493,538 +10,847	+2%	+$594K	0.01%	1741
2013 Q4	$23.9M	Buy	482,691 +11,612	+2%	+$704K	0.01%	1892
2013 Q3	$36.7M	Buy	471,079 +48,382	+11%	+$3.98M	0.01%	1558
2013 Q2	$38.2M	Buy	+422,697	New	+$39.4M	0.01%	1420